An optical coherence tomography (OCT) imaging apparatus can obtain a tomographic image that visualizes an internal structure of a target to be captured based on the principle of optical coherence tomography (OCT). The OCT imaging apparatus enables an eye doctor or any other specialist to diagnose the stage of a disease while viewing an internal structure of an eyeball.
The OCT imaging apparatus can be used to irradiate an ocular fundus with signal light to obtain information indicating an internal structure in the depth direction at the irradiated position. In this case, the OCT imaging apparatus performs scanning, which is generally known as “B-scan”, to obtain a two-dimensional tomographic image of a predetermined cross section of the target to be captured by irradiating a plurality of linearly arrayed positions of the ocular fundus with the above-described signal light.
Further, the OCT imaging apparatus can perform scanning by irradiating a plurality of positions with light in a two-dimensional area of an ocular fundus surface. Thus, the OCT imaging apparatus can finally obtain three-dimensional volume data of the retina.
In a diagnostic observation, comparing two-dimensional tomographic images captured at a plurality of cross sections of a retina is effective to obtain a sufficient amount of information usable in the diagnosis. A conventional technique discussed in Patent Literature 1 allows an operator to designate a target cross section on a fundus image to switch (select) a tomographic image to be displayed on a screen. Further, a conventional technique discussed in Patent Literature 2 can simultaneously display a plurality of tomographic images of a target that are mutually different in the direction of B-scan.
However, when two or more tomographic images are simultaneously displayed, it will be unclear for a viewer if the displayed tomographic images are similar to or different from each other in the direction of B-scan relative to the target to be captured unless information indicating differences is specifically mentioned.